1. Ecosystems: What Are They and How Do They Work? Chapter 3 Sections 5-7

2. Soils Origins of soils Origins of soils Soil horizons: O, A, B, and C Soil horizons: O, A, B, and C Soil profiles Soil profiles Infiltration and leaching Infiltration and leaching

3. Wood sorrel Oak tree Wood sorrel Lords and ladies Earthworm Dog violet Mole Millipede Honey fungus Organic debris builds up Moss and lichen Rock fragments Bedrock Immature soil Regolith Young soil Pseudoscorpion Mite Nematode Actinomycetes Fungus Springtail Red earth mite Root system C horizon Parent material B horizon Subsoil A horizon Topsoil Grasses and small shrubs Fern Fig. 3-21, p. 51 O horizon Leaf litter

4. Fig. 3-22, p. 52 Soil Profiles from Different Ecosystems

5. Weak humus- mineral mixture Mosaic of closely packed pebbles, boulders Dry, brown to reddish-brown, with variable accumulations of clay, calcium carbonate, and soluble salts Desert Soil (hot, dry climate) Grassland Soil (semiarid climate) Alkaline, dark, and rich in humus Clay, calcium compounds Fig. 3-22a, p. 52 Soil Profiles from Different Ecosystems

6. Acidic light- colored humus Iron and aluminum compounds mixed with clay Forest litter leaf mold Humus-mineral mixture Light, grayish- brown, silt loam Dark brown Firm clay Acid litter and humus Humus and iron and aluminum compounds Light-colored and acidic Tropical Rain Forest Soil (humid, tropical climate) Deciduous Forest Soil (humid, mild climate) Coniferous Forest Soil (humid, cold climate)

7. pH Acidity or alkalinity of water or water-bearing samples Acidity or alkalinity of water or water-bearing samples Scale 0-14 Scale 0-14 Acidic: pH 0-6.9 Acidic: pH 0-6.9 Neutral pH 7.0 Neutral pH 7.0 Alkaline (basic): pH 7.1-14 Alkaline (basic): pH 7.1-14

8. pH Scale

9. Matter Cycling in Ecosystems: Biogeochemical Cycles Nutrient (biogeochemical) cycles Nutrient (biogeochemical) cycles Hydrologic (water) cycle Hydrologic (water) cycle Carbon cycle Carbon cycle Nitrogen cycle Nitrogen cycle Phosphorus cycle Phosphorus cycle Sulfur cycle Sulfur cycle

10. Precipitation to land Evaporation From ocean Ocean storage Condensation Transpiration Rain clouds Infiltration and percolation Transpiration from plants Groundwater movement (slow) Precipitation Simplified Hydrologic (Water) Cycle Fig. 3-24, p. 54 Surface runoff (rapid) Evaporation From ocean Rapid Precipitatio n to ocean Surface runoff (rapid)

11. Human Intervention in the Hydrologic Cycle Large withdraw of surface and ground waters Large withdraw of surface and ground waters Clearing vegetation Clearing vegetation Pollution Pollution

12. Diffusion between atmosphere and ocean Carbon dioxide dissolved in ocean water Marine food webs Producers, consumers, decomposers, detritivores Marine sediments, including formations with fossil fuels Combustion of fossil fuels Fig. 3-25a, p. 56 The Carbon Cycle (Marine) sedimentation uplifting over geologic time photosynthesis aerobic respiration death, sedimentation incorporation into sediments

13. Atmosphere (most carbon is in carbon dioxide) Terrestrial rocks Land food webs Producers, consumers, decomposers, detritivores Peat, fossil fuels Soil water (dissolved carbon) Combustion of fossil fuels volcanic action Fig. 3-25b, p. 57 The Carbon Cycle (Terrestrial) photosynthesis death, burial, compaction over geologic time aerobic respiration deforestaion combustion of wood (for clearing land; or fuel) weathering leaching, runoff

14. Fig. 3-26, p. 56 High projection Low projection Human Interference in the Global Carbon Cycle

15. Gaseous Nitrogen (N2) in Atmosphere Nitrogen Fixation by industry for agriculture Food Webs on Land Fertilizers uptake by autotroph s excretion, death, decomposition uptake by autotroph s Nitrogenous Wastes, Remains in Soil NO 3 – in Soil NO 2 – in Soil loss by leaching 1. Nitrification bacteria convert NH 4 + to nitrite (NO 2 – ) 2. Nitrification bacteria convert NO 2 – to nitrate (NO 3 – ) Ammonification bacteria, fungi convert the residues to NH 3 ; this dissolves to form NH 4 + NH 3, NH 4 + in Soil loss by leaching Nitrogen Fixation bacteria convert N 2 to ammonia (NH 3 ); this dissolves to form ammonium (NH 4 + ) Denitrification by bacteria Fig. 3-27, p. 58 The Nitrogen Cycle

16. Fig. 3-28, p. 58 Nitrogen fixation by natural processes Nitrogen fixation by processes human Human Interference in the Global Nitrogen Cycle

17. Marine Sediments Rocks Marine Food Webs Dissolved in Ocean Water Dissolved in Soil Water, Lakes, Rivers Land Food Webs Guano Fertilizer excretion uptake by autotrophs death, decomposition sedimentation settling out uplifting over geologic time weathering uptake by autotrophs weathering mining leaching, runoff agriculture Fig. 3-29, p. 59 The Phosphorus Cycle

18. Ocean Hydrogen sulfide Industries Volcano Oxygen Water Ammonia Sulfur trioxideSulfuric acid Acidic fog and precipitation Ammonium sulfate Plants Animals Sulfate salts Hydrogen sulfide Sulfur Decaying matter Metallic Sulfide deposits Dimethyl sulfide Sulfur dioxide Fig. 3-30, p. 60 The Sulfur Cycle